Polyacrylamide Based Polymers: Smart Materials Used in Wastewater Treatment

2020 ◽  
Vol 12 (1) ◽  
pp. 105-107 ◽  
Author(s):  
Amar Nath ◽  
P. P. Pande
Keyword(s):  
Wastewater Treatment ◽  
Smart Materials ◽  
Chemical Properties ◽  
Industrial Effluents ◽  
Solid Residue ◽  
Natural Polymers ◽  
High Affinity ◽  
Physico Chemical ◽  
Materials Used ◽  
Very High

Now-a-days synthetic polyelectrolytes are frequently used by the industries in the treatment of industrial effluents. Such materials have a variety of properties such as easily changeable structure as per the specific requirement, higher purity, highstability and have more efficiency than the natural polymers. These polymers do not add any solid residue in the sludge, exhibit no change in the physico-chemical properties of the treated water and therefore this water may be recycled. Polyacrylamide is a synthetic polyelectrolyte which is hydrophilic in nature and insoluble in organic solvents. It has very high affinity towards the suspended particles present in water. Therefore, polyacrylamide based polymers are highly effective for the flocculation of suspended contaminated particle present in the effluents. Polyacrylamide is very important polymer for wastewater treatment which enhances the flocculation potential by modification of its nature into non-ionic, anionic and cationic forms.

scholarly journals Experimental and Physico-Chemical Comparison of ZnO Nanoparticles’ Activity for Photocatalytic Applications in Wastewater Treatment

Catalysts ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 678
Author(s):  
Stefano Alberti ◽  
Irene Basciu ◽  
Marco Vocciante ◽  
Maurizio Ferretti
Keyword(s):  
Wastewater Treatment ◽  
Zno Nanoparticles ◽  
Energy Dispersive Spectrometer ◽  
Chemical Properties ◽  
X Ray Diffraction ◽  
Commercial Sample ◽  
Synthetic Process ◽  
Physico Chemical ◽  
Photocatalytic Applications ◽  
Reflectance Measurements

In this contribution, the photoactivity upon activation by simulated sunlight of zinc oxide (ZnO) obtained from two different synthetic pathways (Acetate and Nitrate) is investigated for water purification. Different reagents and processes were exploited to obtain ZnO nanoparticles. Products have been characterized by means of X-Ray Diffraction, Scanning Electron Microscopy along with Energy Dispersive Spectrometer, Dynamic Light Scattering, and Diffuse Reflectance Measurements, to highlight the different outcomes ascribable to each synthesis. A comparison of characteristics and performances was also carried out with respect to commercial ZnO. Nanoparticles of this semiconductor can be obtained as aggregates with different degrees of purity, porosity, and shape, and their physical-chemical properties have been addressed to the specific use in wastewater treatment, testing their effectiveness on the photocatalytic degradation of methylene blue (MB) as a model pollutant. Excluding the commercial sample, experimental results evidenced a better photocatalytic behavior for the ZnO Nitrate sample annealed at 500 °C, which was found to be pure and stable in water, suggesting that ZnO could be effectively exploited as a heterogeneous photocatalyst for the degradation of emerging pollutants in water, provided that thermal treatment is included in the synthetic process.

Concepts and methodologies to minimize pollutant discharge for zero-emission production

1999 ◽  
Vol 39 (10-11) ◽  
pp. 9-16 ◽  
Author(s):  
Hong-Ying Hu ◽  
Naohiro Goto ◽  
Koichi Fujie
Keyword(s):  
Wastewater Treatment ◽  
Production Process ◽  
Molecular Size ◽  
Preliminary Evaluation ◽  
Flow Sheet ◽  
Production Processes ◽  
Physico Chemical ◽  
Materials Used ◽  
Pollutant Discharge ◽  
Novel Concept

The present study aims to present basic concepts to minimize the emissions from industrial production processes. Strategies and methodologies to analyze emissions from various production processes, to establish a so called negative flow sheet and to reduce the emissions from those processes by refining and/or replacing the present production process with an alternative process are discussed. Preliminary evaluation and management systems of the materials used in the production process based on characteristics such as microbial and physico-chemical treatabilities are proposed as well. The relationship between the removal efficiency of dissolved organic carbon in the five-days BOD test and that in a laboratory scale submerged biofilter with continuous operation is suggested to evaluate the biological removability of organic pollutants contained in wastewater. A novel concept to select the appropriate treatment process of an industrial wastewater based on properties such as the molecular size and biodegradability of the pollutants contained in that wastewater is also proposed. To give basic information for the minimization of energy consumption in wastewater treatment, various biological wastewater treatment processes are compared from the view point of power economy.

Natural mixture of silica and smectite as a new clayey material for industrial applications

Clay Minerals ◽  
2009 ◽  
Vol 44 (4) ◽  
pp. 525-537 ◽  
Author(s):  
U. Sohling ◽  
F. Ruf ◽  
K. Schurz ◽  
K. Emmerich ◽  
A. Steudel ◽  
...  
Keyword(s):  
Protein Separation ◽  
Amorphous Material ◽  
Chemical Properties ◽  
Industrial Applications ◽  
High Porosity ◽  
Clayey Material ◽  
Physico Chemical ◽  
Natural Mixture ◽  
Biodiesel Purification ◽  
Very High

AbstractThe main physico-chemical properties of a new smectitic clay containing large amounts of amorphous material are reviewed and potential industrial applications of this type of clay are discussed. Due to a 34% amorphous material content (natural silica gel), the investigated clay has very high porosity and can be used as it is or in acid-impregnated form for oil bleaching or phosphate reduction in edible oil. In the field of biodiesel purification, the new clay can be used to remove, in particular, mono-, diglycerides and glycerol. The natural silica-smectite mixture is also suitable as a carrier for liquid ingredients, for example in animal feeds, and might serve as a partial or complete substitute for synthetic precipitated silicas. In the field of bioseparation processes, the clay can be used as an adsorbent for protein separation by means of cation exchange. Due to the suppressed swelling (compared with smectite alone), it can be packed in columns which can be regenerated.

Effects of Industrial Effluents on the Population Density of Soil Microarthropods

1978 ◽  
Vol 5 (3) ◽  
pp. 229-231 ◽  
Author(s):  
Udai Raj Singh ◽  
B. D. Tripathi
Keyword(s):  
Population Density ◽  
Chemical Properties ◽  
Industrial Effluents ◽  
Ion Concentration ◽  
Present Communication ◽  
Hydrogen Ion Concentration ◽  
Soil Microarthropods ◽  
Physico Chemical ◽  
Total Fauna ◽  
Water Holding

The present communication gives the results of a quantitative study of soil microarthropods in relation to pollution induced by a chemical and fertilizer factory at Sahupuri, Varanasi, India. The effluent discharged from the factory has been reported to affect adversely the physicochemical properties (porosity, water-holding capacity, hydrogen ion concentration, total nitrogen, exchangeable sodium, and carbonate) of the soil. The samples were processed in Ladell's apparatus by modified floatation technique for faunal estimation. The population density of soil microarthropods has been found to be poor in the effluent-affected soil (28,107/m2) as against the control soil (39,217/m2) of a near-by area. The Acarina formed the most prevalent group in both the control and polluted habitats, constituting 47.8% and 53.6% of the total fauna, respectively. The abnormal physico-chemical properties of the soil have been indicated as being partly responsible for the faunal depletion.

scholarly journals CeO2-Blended Cellulose Triacetate Mixed-Matrix Membranes for Selective CO2 Separation

Membranes ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 632 ◽  
Author(s):  
Chhabilal Regmi ◽  
Saeed Ashtiani ◽  
Zdeněk Sofer ◽  
Zdeněk Hrdlička ◽  
Filip Průša ◽  
...  
Keyword(s):  
Gas Permeability ◽  
Chemical Properties ◽  
Cellulose Triacetate ◽  
Ceo2 Nanoparticles ◽  
Mixed Matrix Membranes ◽  
Co2 Separation ◽  
Mixed Matrix ◽  
High Affinity ◽  
Physico Chemical ◽  
Carbon Dioxide Co2

Due to the high affinity of ceria (CeO2) towards carbon dioxide (CO2) and the high thermal and mechanical properties of cellulose triacetate (CTA) polymer, mixed-matrix CTA-CeO2 membranes were fabricated. A facile solution-casting method was used for the fabrication process. CeO2 nanoparticles at concentrations of 0.32, 0.64 and 0.9 wt.% were incorporated into the CTA matrix. The physico-chemical properties of the membranes were evaluated by SEM-EDS, XRD, FTIR, TGA, DSC and strain-stress analysis. Gas sorption and permeation affinity were evaluated using different single gases. The CTA-CeO2 (0.64) membrane matrix showed a high affinity towards CO2 sorption. Almost complete saturation of CeO2 nanoparticles with CO2 was observed, even at low pressure. Embedding CeO2 nanoparticles led to increased gas permeability compared to pristine CTA. The highest gas permeabilities were achieved with 0.64 wt.%, with a threefold increase in CO2 permeability as compared to pristine CTA membranes. Unwanted aggregation of the filler nanoparticles was observed at a 0.9 wt.% concentration of CeO2 and was reflected in decreased gas permeability compared to lower filler loadings with homogenous filler distributions. The determined gas selectivity was in the order CO2/CH4 > CO2/N2 > O2/N2 > H2/CO2 and suggests the potential of CTA-CeO2 membranes for CO2 separation in flue/biogas applications.

Characterisation of Mg-Zn-Ca-Y powders manufactured by mechanical milling

2020 ◽  
Vol 2 (103) ◽  
pp. 49-59
Author(s):  
S. Lesz ◽  
T. Tański ◽  
B. Hrapkowicz ◽  
M. Karolus ◽  
J. Popis ◽  
...  
Keyword(s):  
Particle Size ◽  
Magnesium Alloys ◽  
Chemical Properties ◽  
Grain Structure ◽  
X Ray Diffraction ◽  
Specific Chemical ◽  
Fine Grain ◽  
Physico Chemical ◽  
Very High ◽  
Xrd Method

Purpose: This paper explains mechanical synthesis which uses powders or material chunks in order to obtain phases and alloys. It is based on an example of magnesium powders with various additives, such as zinc, calcium and yttrium. Design/methodology/approach: The following experimental techniques were used: X-ray diffraction (XRD) method, scanning electron microscopy (SEM), determining particle size distributions with laser measuring, Vickers microhardness. Findings: The particle-size of a powder and microhardness value depend on the milling time. Research limitations/implications: Magnesium gained its largest application area by creating alloys in combination with other elements. Magnesium alloys used in various industry contain various elements e.g. rare-earth elements (REE). Magnesium alloys are generally made by casting processes. Consequently, the search for new methods of obtaining materials such as mechanical alloying (MA) offers new opportunities. The MA allows for the production of materials with completely new physico-chemical properties. Originality/value: Thanks to powder engineering it is possible to manufacture materials with specific chemical composition. These materials are characterized by very high purity, specified porosity, fine-grain structure, complicated designs. These are impossible to obtain with traditional methods. Moreover it is possible to refine the process even further minimalizing the need for finishing or machining, making the material losses very small or negligible. Furthermore material manufactured in such a way can be thermally or chemically processed without any problems.

scholarly journals Modified lead dioxide for organic wastewater treatment: Physicochemical properties and electrocatalytic activity

2019 ◽  
Vol 84 (2) ◽  
pp. 187-198 ◽  
Author(s):  
Olesia Shmychkova ◽  
Tatiana Luk’yanenko ◽  
Larisa Dmirtikova ◽  
Alexander Velichenko
Keyword(s):  
Wastewater Treatment ◽  
Physicochemical Properties ◽  
Electrochemical Oxidation ◽  
Oxygen Evolution ◽  
Electrocatalytic Activity ◽  
Lead Dioxide ◽  
Chemical Properties ◽  
Destruction Rate ◽  
Physico Chemical ◽  
Pbo2 Anode

An investigation is reported on lead dioxide electrodeposition from methanesulfonate electrolytes additionally containing Ni2+ ions. It is shown that lead dioxide electrodes micromodified by nickel have different physico-chemical properties vs. nonmodified PbO2-anodes that are formed during the deposition. Electrocatalytical reactivity of electrodes involved in comparison to both the oxygen evolution, as well as to the electrooxidation of 2,4- dichlorophenoxyacetic (2,4-D) acid is investigated. Processes of electrochemical oxidation of 2,4-D on various materials occur qualitatively with the same mechanism and differ only in the rate. It is shown that the Ni-PbO2-anode possesses the highest electrocatalytic activity: the destruction rate of 2,4-D on it increases in 1.5 times in comparison with nonmodified lead dioxide. The COD of a 0.4 mM solution of 2,4-D, determined by the dichromate method, is 90.0 mg dm-3 which is 94 % of the theoretical value.

scholarly journals Physico-chemical characterization of some selected soil series of Mymensingh and Jamalpur districts of Bangladesh

2016 ◽  
Vol 13 (2) ◽  
pp. 197-206
Author(s):  
PR Sheel ◽  
MAH Chowdhury ◽  
M Ali ◽  
MA Mahamud
Keyword(s):  
Sandy Loam ◽  
Chemical Properties ◽  
Chemical Characterization ◽  
Agricultural Practices ◽  
Soil Series ◽  
Total N ◽  
Positive Correlation ◽  
Physico Chemical ◽  
Very High

The soil physico-chemical properties have been disturbed due to long continued intensive agricultural practices. Under this situation we are approaching rapidly to a very strong future challenge in sustaining the quality of our soil. This study was conducted to evaluate the physico-chemical properties of the selected soil series. The area covered Mymensingh and Jamalpur districts of Bangladesh. Soil samples were collected randomly from different profiles of Lokdeo, Tarakanda, Silmondi and Melandah soil series during March-May, 2014 and analysed. All soils were acidic and textural classes were sandy loam, silt loam, loam, and clay loam. Organic matter and total N contents low to very low. Available S content in the upper layers of most soils were medium to optimum and in the deeper layer low to medium. The exchangeable K, Ca and Na contents were also low. The upper layers of all the locations contained higher amounts of available Zn. The available Cu and Fe contents of most soils were very high. The soils of all locations contained very high amount of available Mn except the deeper layers (45-75 cm) of Melandah which contained optimum amount of available Mn. Soil pH showed negative correlation with total N and available S. Total N showed positive correlation with soil OM, available Cu and available S. There was positive correlation between available S and available Mn.J. Bangladesh Agril. Univ. 13(2): 197-206, December 2015

scholarly journals New Developments in Medical Applications of Hybrid Hydrogels Containing Natural Polymers

Molecules ◽  
2020 ◽  
Vol 25 (7) ◽  
pp. 1539 ◽  
Author(s):  
Cornelia Vasile ◽  
Daniela Pamfil ◽  
Elena Stoleru ◽  
Mihaela Baican
Keyword(s):  
Biomedical Applications ◽  
Chemical Properties ◽  
Synthetic Polymers ◽  
Point Of View ◽  
Natural Polymers ◽  
New Developments ◽  
Organic Hybrid ◽  
Hybrid Hydrogels ◽  
Physico Chemical ◽  
Polymeric Hydrogels

New trends in biomedical applications of the hybrid polymeric hydrogels, obtained by combining natural polymers with synthetic ones, have been reviewed. Homopolysaccharides, heteropolysaccharides, as well as polypeptides, proteins and nucleic acids, are presented from the point of view of their ability to form hydrogels with synthetic polymers, the preparation procedures for polymeric organic hybrid hydrogels, general physico-chemical properties and main biomedical applications (i.e., tissue engineering, wound dressing, drug delivery, etc.).

On diastereomeric perturbations

2000 ◽  
Vol 78 (6) ◽  
pp. 816-828 ◽  
Author(s):  
Christian Girard ◽  
Henri B Kagan
Keyword(s):  
Asymmetric Synthesis ◽  
High Selectivity ◽  
Enantiomeric Excess ◽  
Chemical Properties ◽  
Nonlinear Effects ◽  
Minimum Condition ◽  
Living Matter ◽  
Physico Chemical ◽  
The Common ◽  
Very High

For more than a century, organic chemists have been playing in Nature's laboratory. Their first goal was to understand the organization of atoms in the living matter and then to reproduce it by synthesis. This quest gave rise to several efficient techniques to synthesise molecules; many of them still in use nowadays, as such or with little modifications. Even at the beginning of this journey, the chemists discovered that their methods were far from being as efficient as the ones used by Nature to produce substances. The natural molecules were chiral and there was even an enantiomer that was produced over the other;a lesson of perfection. This was another challenge for the chemists and they succeeded by first developing techniques to separate enantiomers and more recently reagents and reactions to produce only the desired stereoisomer. Asymmetric synthesis uses chiral auxiliaries, reagents or catalysts to create chirality into the desired compound. The common perception, as a minimum condition, was that the chiral substance used to perform such a transformation has to be of the highest enantiomeric purity to obtain a very high selectivity. The relation between the enantiomeric excesses of the chiral substance and the product was suggested to be linear. But there were a lot of surprises left in the laboratory. Who would have thought that an impure substance could give an enantiomeric excess in the product higher than its own purity? The molecules are acting in different ways in solution. Self-organization and aggregation can arise depending on the structure of the substance or its environment. Such phenomenon can generate deviations to the awaited behaviour of the molecules that can be observed in many cases. This article tries to present some examples of the historical reports of such peculiar behaviours, their influence on physico-chemical properties and the final discovery of the now well-known nonlinear effects in asymmetric synthesis.Key words: asymmetric synthesis, diastereomeric interactions, nonlinear effects.

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